So, is this really something new for Android? I'm not trying to be antagonistic or deliberately obtuse here, I really don't know. I know there have been SMS apps for the iPad since last year.

I'm not sure if you don't understand this premise but Android tablets until recently don't have data capabilities except wifi so using them over a cell network isn't possible and thus not able to receive/send phone calls or sms messages.

This program allows that cross over so your tablet doesn't need to have cell data to do things that you want. Just like if you want you can tether your phone to your tablet and use that for data.